Exemplary embodiments of the present invention relate to a semiconductor device fabrication technology, and more particularly, to a resistive memory device using a resistance change in detecting data, such as a nonvolatile resistive random access memory (ReRAM) and a method for fabricating the same.
Next generation memory devices which can replace a dynamic random access memory (DRAM) and a flash memory are being developed. One of such next generation memory devices is a resistive memory device using a resistive layer. Specifically, a resistive memory device uses a material whose resistance rapidly changes according to a bias applied thereto and thus can switch between at least two different resistance states.
According to an example, a resistive memory device includes a resistive element and a selection element. The resistive element includes a lower electrode, a resistive layer, and an upper electrode, which are sequentially formed on a substrate. A filament current path is formed or removed within the resistive layer of the resistive element according to biases applied to the upper electrode and the lower electrode, and data is stored according to a resistance state which depends on the formation and removal of the filament current path.
Therefore, the resistive memory device may have a large sensing current and may be sensitive to a resistance. Here, as the effective area of the resistive element becomes larger, a characteristic of the resistive element is degraded. Thus, methods for reducing the effective area of the resistive element are useful.
Reducing an area of a resistive element is difficult. Further, in reducing the area of the resistive element, the area of the selection element may also be reduced and thus the resistance of the selection element may be increased. Therefore, an electric field and a current required upon a switching operation may not be appropriately supplied to the resistive element.